Dr Joe;936504; said:
(and forget ever having anything stay in the same place in the tank)
Word!
Males dig themselves huuuge pits to spawn in. One of my females gave me a good scare when she went male-pitch black and dug a big pit to spawn with herself.
I've got 4 ~3" males (and 3 same size females, all from my last spawn before I sold off dad) and they've got several pits in their tank. Always fighting. If I don't separate them soon I'll only have one male left by the time they reach about about 5". My dominant male was just that, an obviously dominant male, by the time he was 1". Grew much faster and larger than his broodmates and at his tiny size was already hitting a striated blue/green-black body & green cheeked colors, developing the ducky lips and digging 3" pits. Inherited his dad's mojo

. I was able to sex the other males at 2" but they didn't start changing their shape till I separated all the males from the females.
Sexing them is usually pretty basic. Males are more colorful and have differently shaped mouths and heads but it can get tricky.
Subdom males can keep their female looks for as long as they can if there's already a dominant male with them pushing his weight around. They still usually have more of a blue/green patterned sheen to them and IMO bluer lips so it gets easier to spot them with a trained eye.
Females can go dark as well, almost fully mimicking spawning male coloration with white patches on the cheeks but the patches aren't really as clean as those on males.
You can grow a large batch together in a huge tank and you'll get males that look like females till they reach adult size and once you pull them it's like they automatically start transformation. Their heads and mouths flatten out and lips start curving slightly upwards. Pretty awesome.